This invention relates to limited flow cups.
Dysphagia, a condition characterized by difficulty in swallowing food and liquids, can be present in patients suffering from stroke, head injury, neurological disorders, and other cognitive and motor problems. It may also occur as a result of aging, disability, or as a transient condition following some surgeries. As a result of dysphagia, patients may also suffer from dehydration and nutritional deficits.
When a person suffering from dysphagia attempts to swallow thin liquids, the bolus may tend to go down the bronchus and into the lungs, causing coughing, choking and even aspiration, which can lead to pneumonia. In order to maintain nutrition and hydration, these patients are sometimes given very small volumes, typically about one teaspoon. These smaller boluses can be more readily handled, often without aspiration problems.
Various devices, liquid thickeners and other products have previously been developed to assist patients with dysphagia, but these typically do not allow a fixed volume to be delivered, with a normal drinking motion, without the assistance of a caregiver.
Limited flow drinking cups are designed to provide a fixed, metered amount of liquid to a user. A typical limited flow cup includes a cup body having a cover that defines an opening through which fluid can pass. Metering is provided by a three-piece assembly including (a) the cover, (b) a tube that is fixed to the cover at the opening and extends downward into the cup body, and (c) a tiny, self-contained metering cup mounted at the lower end of the tube. The metering cup has an open end that faces in a generally sideways direction. Prior to drinking, the cup body contains liquid up to a given liquid level, the metering cup is full of liquid, and the tube is filled with liquid up to the liquid level within the cup body. The metering cup and the portion of the tube that is below the liquid level in the cup body together define a metering chamber having a limited volume. When the user tilts the limited flow cup to a drinking position, the liquid within the metering chamber flows through the tube and out through the opening to the user. When the cup body is in the drinking position, the open end of the metering cup generally extends above the liquid level within the cup body, so that fluid cannot flow into the metering cup. As a result, only the volume within the metering chamber is dispensed during a single drinking motion.
The present invention features a limited flow cup that has a metering chamber that is defined by a nested relationship between a pair of cups. The nested arrangement allows the metering chamber to be defined by components that do not include any closed features, such as tubes, and provides a device that does not include any small or moving parts. The lack of closed features allows the cups to be readily molded. Ease of molding is further facilitated by the simple shape of the cups, which allows them to release relatively easily from a mold. As a result, the limited flow cup is generally economical to manufacture, e.g., by injection molding. The lack of small and moving parts allows the cup to be easily assembled both during manufacturing and prior to use by the user or a caregiver, and makes the cup relatively resistant to failure or damage. The cup is also easy for the user to correctly assemble and use. Additionally, the lack of closed features, which are typically difficult to clean, allows the limited flow up to be kept clean and sanitary, e.g., by simply disassembling the nested cups and washing them in a dishwasher.
In one aspect, the invention features a limited flow cup, including a first cup, a second cup, in nested relationship with the first cup, and a fluid reservoir, the nested relationship of the first cup and second cup defining a metering chamber, in fluid communication with the reservoir, constructed to contain an amount of fluid for delivery to a user during a drinking motion, the metering chamber being configured to restrict the amount of fluid delivered to a user when the limited flow cup is tilted during the drinking motion.
Some implementations of this aspect of the invention may include one or more of the following features.
The metering chamber includes an inlet through which fluid can flow from the fluid reservoir to the metering chamber, the inlet being configured to allow entry of fluid from the reservoir into the metering chamber when the limited flow cup is in a first position, and restrict entry of fluid from the reservoir into the metering chamber when the limited flow cup is in a second, tilted position. The inlet is positioned so that it will be above the liquid level in the fluid reservoir when the limited flow cup is tilted during the drinking motion. The metering chamber includes a cavity and an elongated fluid passage in fluid communication with the cavity.
In some implementations, the first cup includes an outer cup, the second cup includes an inner cup, disposed within the outer cup, and the inner cup defines the fluid reservoir. The cavity is defined by an indentation in a lower surface of the inner cup, and a lower surface of the outer cup. The elongated fluid passage is defined by a channel extending into the inner cup, and a ridge protruding from an inner wall of the outer cup. The cavity includes an opening to allow fluid to flow into the cavity from the reservoir. The opening is in a side surface of the cavity, and the opening extends to a lower surface of the inner cup to allow for delivery of essentially all of the liquid in the reservoir. The limited flow cup further includes a cover that sealingly engages the rims of the inner and outer cups and defines an opening through which the user can drink the liquid. A lower surface of the cover defines an annular channel that, when the cover is in place, is in fluid communication with the metering chamber. The cover defines one or more apertures that communicate between the ambient air and the annular channel, allowing air to enter the annular channel. The cover further defines a drinking spout, and the aperture(s) allow sufficient air to enter the annular channel so that a user of the limited flow cup is hindered from withdrawing fluid from the limited flow cup by sucking on the drinking spout.
Alternatively, the limited flow cup further includes an outer cup that defines the fluid reservoir, and the first cup and second cup are disposed within the outer cup. The cavity is defined between bottom walls of the first and second cups, and the fluid passage is defined between side walls of the first and second cups. The first cup includes an opening to allow fluid to flow into the cavity from the reservoir. The opening is in a side surface of the first cup, and the opening extends up the side surface a sufficient distance to allow for delivery of essentially all of the liquid in the reservoir. The second cup includes a cover portion that defines an opening through which the user can drink the liquid. The first cup includes a rim portion that sealingly engages a peripheral edge of the cover portion. The rim portion also sealingly engages a rim of the second cup. The cover portion and an upper wall of the first cup together define an annular channel that, when the cover is in place, is in fluid communication with the metering chamber. The cover portion defines one or more apertures that communicate between the ambient air and the annular channel, allowing air to enter the annular channel. The cover portion further defines a drinking spout, and the aperture(s) allow sufficient air to enter the annular channel so that a user of the limited flow cup is hindered from withdrawing fluid from the limited flow cup by sucking on the drinking spout.
The limited flow cup further includes a pair of regions constructed to receive a corresponding pair of handles. The limited flow cup further includes a handle constructed to be received by the regions and thereby securely attached to the limited flow cup. The volume of the metering chamber is from about 4.5 to 5.5 ml. The volume of the cavity is from about 3 to 5 ml. The volume of the elongated fluid passage is less than about 25% of the total volume of the metering chamber. The volume of the metering chamber is less than 10% of the volume of the fluid reservoir. The amount of fluid delivered to the user when the fluid reservoir is 10% full varies by no more than 25% from the volume delivered when the fluid reservoir is 100% full. The cover defines a headspace volume that is from about 28% to 40% of the volume of the inner cup. The amount delivered to the user when the reservoir is 100% full will be less than or equal to the volume of the metering chamber. The amount delivered to the user immediately after the reservoir is initially filled by the user will be less than or equal to the volume of the metering chamber.
The outer cup and inner cup include corresponding structures to prevent the outer cup from being used without the inner cup in nested arrangement with the outer cup. The outer cup includes an aperture in a lower surface of the outer cup, through which liquid will flow if the outer cup is filled with liquid without the inner cup in nested arrangement with the outer cup. The inner cup includes a plug extending from its lower surface, the plug being positioned to seal the aperture in the lower surface of the outer cup when the inner and outer cups are properly nested. Alternatively, the aperture in the outer cup includes a raised rim, and the inner cup includes a recess that is constructed to seal around the raised rim and over the aperture when the inner and outer cups are properly nested.
In a further aspect, the invention features a limited flow cup, including (a) a first cup, (b) a second cup, in nested relationship with the first cup, (c) a fluid reservoir, the nested relationship of the first cup and second cup defining a metering chamber, in fluid communication with the reservoir, constructed to contain an amount of fluid for delivery to a user during a drinking motion, and (d) a cover, the cover including an aperture through which the liquid can be delivered to the user.
Some implementations include one or more of the following features. The cover is integral with one of the first and second cups. The cover includes a rim that sealingly engages a rim of one of the first and second cups to provide a fluid tight seal. The metering chamber includes an inlet through which fluid can flow from the fluid reservoir to the metering chamber, the inlet being positioned so that it will be above the liquid level in the fluid reservoir when the limited flow cup is tilted sufficiently to allow fluid to flow from the aperture.
In another aspect, the invention features a limited flow cup for dispensing a limited volume of liquid to a user each time the limited flow cup is tilted to a drinking position, the limited flow cup including: (a) an outer cup, (b) an inner cup, nested within the outer cup, for containing a supply of the liquid, and (c) a cover that is constructed to be sealingly applied to the outer cup and inner cup, the cover including an aperture through which the liquid can be delivered to the user. The outer cup and inner cup have adjacent spaced surfaces that together define a metering chamber that includes a cavity, and an elongated fluid passage in fluid communication between the cavity and the aperture. The cavity includes an inlet through which fluid can flow from the inner cup to the cavity, the inlet being positioned so that it will be above the liquid level in the inner cup when the inner cup is tilted sufficiently to allow fluid to flow from the aperture.
In another aspect, the invention features a limited flow cup for dispensing a limited volume of liquid to a user each time the limited flow cup is tilted to a drinking position, the limited flow cup including: (a) an outer cup for containing a supply of the liquid, (b) a middle cup, nested within the outer cup, and (c) an inner cup, nested within the middle cup, the inner cup including a cover portion that includes an aperture through which the liquid can be delivered to the user. The middle cup and inner cup have adjacent spaced surfaces that together define a metering chamber that includes a cavity, and an elongated fluid passage in fluid communication between the cavity and the aperture. The cavity includes an inlet through which fluid can flow from the outer cup to the cavity, the inlet being positioned so that it will be above the liquid level in the outer cup when the limited flow cup is tilted sufficiently to allow fluid to flow from the aperture.
In yet a further aspect, the invention features a limited flow cup including a pair of nesting inner and outer cups, the inner and outer cups being constructed to be nested and disassembled by a user, allowing easy cleaning, and the nested arrangement of the cups defining a fluid passage that does not exist when the cups are disassembled.
In some implementations, the inner and outer cups do not include any closed features.
Preferred limited flow cups of the invention include an xe2x80x9canti-suckxe2x80x9d feature (e.g., the apertures in communication with the annular channel, described above) that impedes the user from circumventing the metering function by sucking fluid out of the cup. Thus, in such cups the metering feature generally cannot be circumvented by applying mouth suction to the hole in the lid of the cup through which the user drinks.
Some preferred cups do not require the person filling the cup with liquid to follow any special or non-obvious steps, such as filling the cup so that liquid stays below a fill line or mark on the cup, steps which may be difficult for caregivers to remember. Such preferred cups are also designed to meter fluid even when filled to the rim of the cup, while still maintaining an aesthetic cup shape, as will be discussed in detail below. The ability of the cup to function properly when filled to the rim ensures that a metered volume will be delivered each time the user drinks from the cup, including the first drink when the cup is at its fullest. This assurance of first-pour functioning is very important in dysphagia applications, due to the grave consequences that may result from receiving too large a volume of liquid even once.
In some implementations the assembled cup is generally spill-proof, with only a single metered volume of liquid exiting the cup when it is inadvertently knocked on its side.
Other features and advantages of the invention will be apparent from the description and drawings, and from the claims.